1. Technical Field
The present invention relates generally to telephony systems, and methods of call routing in conference calls. More particularly the invention relates to a system and method of mass dialing telephone conference participants using an advanced call routing system, to determine the least expensive carrier for each call.
2. Description of the Related Art
In telephony systems, a location routing number (LRN) is a unique number that has the format of a telephone number (TN), but represents an entire telephone switch through which multiple telephone numbers (TNs) are routed. In the United States, the LRN is a 10-digit number which follows the North American Numbering Plan (NANP). The LRN is stored in a database called a Service Control Point (SCP), which identifies a switching port for a local telephone exchange.
When a telephone number (TN) is dialed, since individual TNs are mapped to an LRN (referred to as a “subscription”), the local telephone exchange queries or “dips” a routing database, usually the SCP, for the LRN associated with the subscriber. The LRN removes the need for a public telephone number to identify the local exchange carrier.
Presently, subscribers want local number portability (LNP), which means that when a subscriber's phone service is moved from one service provider to another, the telephone number (TN) does not change. This process is called “porting” a number. Every ported TN must have an LRN assigned to it. Thus, if a subscriber changes to another telephone service provider, the current telephone number (TN) can be retained, and only the LRN needs to be changed. A neutral company has been chartered with developing and maintaining the Number Portability Administration Center (NPAC) to support the implementation of Local Number Portability (LNP).
In addition to supporting service provider phone number portability to a subscriber, an LRN also supports the possibility of two other types of number portability: service portability (for example, ordinary service to ISDN) and geographic portability.
Presently, the particular carrier for an individual call is chosen based on a system called least-cost-routing (LCR). This system is well-known in the art, and is widely used for routing telephone calls by telecommunication companies. In voice telecommunications, LCR is the process of selecting the path of outbound communications traffic based on cost. Within a telecommunications carrier, an LCR team might periodically (monthly, weekly or even daily) choose between routes from several or even hundreds of carriers for destinations across the world. This function might also be automated by a device and/or software program known as a “Least Cost Router”, which performs in real-time.
The portability of telephone numbers impacts the LCR system. In particular, mobile number portability affects internet telephony, voice-over-IP (VoIP) telephony, and LCR companies. Just as it is possible to port a land line telephone number, mobile phone numbers are also portable when changing service providers. With telephone number portability in place around the world, LCR providers can no longer rely on using only a portion of the dialed telephone number to route a call. Instead, they now have to determine the actual current network of every number before routing the call. Thus, LCR solutions also need to handle telephone number portability when routing a voice call.
In mass telephone conferencing systems, it appears that more and more telephone calls are made to ported phone numbers. It is estimated that of the close to 500 million ported telephones in the United States, approximately 40% of telephone calls are made to ported phone numbers. Thus, a method and system of advanced call routing, to ensure that calls are routed to a lower cost carrier, would be advantageous.